Hole-grinding machine.



G. K. GARVIN & E. J. MOOLELLAN.

HOLE GRINDING MACHINE.

APPLICATION FILED AUG. 11, 1911.

1,026,389. Patented May 14, 1912.

3 SHEETS-SHEET 1,.

WITNESSES g I a g C, gVE/VTORS I q t 1/ M M ATTORNEY G. K. GARVIN & E.J. MOGLELLAN. HOLE GRINDING MACHINE.

APPLICATION FILED AUG. 11, 1911.

.1 ,Q26,389. Patented May 14, 1912.

3 SHEETS-SHEET 2.

WITNESSES S INVENTOI? If 0 7? m gmf pg 644.

M ATTORNEY G. K. GARVIN & E. J. MoOLELLAN.

HOLE GRINDING MACHINE.

APPLICATION FILED 16.11, 1911.

Patented May 14, 1912.

3 SHEETS-SHEET 3.

INVENTOR {##y {M M. NIH/HIE)! UNITED sTA Es PATENT OFFICE.

GEORGE K. GARVI [N AND EDWARD J. MoCLELLAN, OF NEW YORK,,N'. Y.,ASSIONORS TO THE GARVIN MACHINE COMPANY, A CORPORATION OF NEW YORK.

HOLE-GRINDING- MACHINE.

Specification of Letters Patent.

Patented May 14, 1912.

To all whom it may concern Be it known that we, Gnonon K. GARVIN.

and EDWARD J. MoCLELLAN, citizens of the United States, residing at NewYork city, in the county of New York and State of New York, have,invented a new and useful Improvement in Hole-Grinding Machines, of"which the following is a specification.

This invention relates to machines for grinding or finishing surfaces,and particularly interior surfaces such as the axial bales of hardenedgears, ball races and the li e.

Still more particularly the invention relates to a machine in which agrinding wheel or element rotates at a high speed,

and 'which is moved longitudinally into and out of a hole to be ground.in such a way that when fully withdrawn from the hole the rotation ofthe work will be stopped and an opportunity given the workman to caliperthe hole.

The invention has for one of its objects a machine which is sensitive,i. e. which is operated by hand manipulation and in which the feel ofthe cut is constantly present in the control by the operator; (inpractice an expert operator proceeds as much by the feel in a sensitivemachine I as by sight.)

Another object of the invention is to provide for a very strong, compactand simple construction which is easily operated and which is ca able ofperforming a Wide range of wor or service.

The invention relates to an im roved machine for grinding holes or suraces in its various aspects.

The invention consists in the features of construction, combination,location and arrangement, as hereinafter set forth.

In the drawings, Figure 1, is a side elevation partly broken away of agrinding machine embodying the principles of this invention; Fig. 2, isa top view of the same; Fig.3,is an end view partly in section, and Fig.4 is a detail view showing a support for the grinding wheel.

Constructions embodying the invention will include a spindle carrying achuck which is adapted to be rotated, and also a spindle carrying agrinding wheel or cutter which rotates at high velocity, preferably ofthe machine.

in a direction contrary to the direction of rotation of the chuckspindle. tion will further include means by which the grinding wheel andspindle may be 'ven a movement so as to cause the grindmg wheel to feedacross the surface of the work which is. being ground.

In the drawings which illustrate the best The inven-.

practical constructions embodying the invention, 1 denotes achuck-spindle, 2 a chuck, 3 a grinding spindle and 4 a grindmg wheelmounted on the grinding spindle.

5 denotes a carriage in which the grind-.

ing spindle is journaled, said carriage having a longitudinal movementin the frame of the machine such frame being denoted 6 in the drawing.

8 denotes the head-stock or journal support for the chuck spindle. Inaccordance with the best constructions embodying the invention, thehead-stock will be adjustable to swivel in different directions in ahorizontal plane, and will be further rovided with a feed by which itmay be given different lateral positions on the bed or frame Asillustrated the headstock has a circular base?) with arc shaped slots10.

11 denotes bolts or screws passed through the arcuate slots 10 and intothe table or transversely movable frame 12. This table or frame 12 hasnarrow ways 13 guided in corresponding ways 14 of the bed.

15 denotes a screw feed with a micrometer adjustment 16, the screw feedacting to position the table 12 and thereby the chuck spindle in anylateral position.

Means may be provided for driving the chuck spindle and also thegrinding spindle, and in the best constructions embodying the inventionwill include a drum 17 in a shaft 18 journaled in bearings 19 within the-frame'6 and below the carriage 5. 20 .de-

notes a shaft which as later described, may

constitute a driving shaft. The latter shaft sired character, and 30denotes a sleeve constituting the driven member of the clutch andseparate from the shaft 20 which constitutes the driving shaft of theclutch.

The sleeve 30 carries a pulley -31 belted by a belt 32to a pulley 33 ofthe chuck spindle 1 through a reducing speed ratio. Means are providedfor engaging and disengaging the elements of the clutch 29 so as to putthis clutch into and out of its driving relation. The meansemployed forthis purpose may vary somewhat in practice, but in accordance with thebest-practical embodiments of the invention, will be controlled from thecarriage 5, and in such a way as to release said clutch only at or nearthe limit of the rearward movement of said carriage...

Referring to the drawings, 35 denotes a segment-gear meshing with a rack36 on the under side of the carriage 5. This segment-gear is fixed to ashaft 38 extending transversely of themachine and having a crank orhandle 40 by which the shaft and thereby the segment-gear are oscillatedand the carriage 5 moved longitudinally of the bed. The carriage 5 has along guide po-rtion41 in order to obtain an arcuate guide and forcertain other purposes'which will later'appear, and it is ordinarilymade as,

light as possible, as of aluminum, and depressed or cut away at 42 inorder to make it as light and sensitive as possible. The depression 42also 'ves a clearance for the swing of the chu 2.- 43 denotes a stop onthe carriage which limits the forward movement thereof and which isadjustable. These details of the carriage may of course vary somewhat inpractice without departing from the spirit and scope of the in vention.I

$5 denotes a pin forming inefiect a crankpin of the gear-segment andhaving depending therefrom a link or pit-man 50 which is in turnconnected to a bell-crank 51 with a fork 52 received in the groove orcollar 53, said collar constituting a member for releasing the clutch 29and being'normally pressed in a direction to tighten said clutch by aspring 55 on the shaft 20. 56 denotes a fixed collar on said shaft totake the thrust of said 5 ring 55.

59 denotes a s 0t in the link or pitman 50,

,the length of which is adjusted by the screw 60, and accordingly thepin 61 of the bell-' crank 51 has a play in its relation to the pitman50 determinedby the length of this slot. The effect is to causeanengagement of the bell-crank and the release of the clutch when thelink 50 has been pulled upnoted that the clutch is re carriage 5 thedisengagement or release of the clutch 29 will stop the rotation of thechuck spindle 1 and permitthe work to be calipered,

Reference has been made to the fact that the movement of the carriageismade light and sensitive, and it is partly for this purpose that thecarriage is made without adjustments such as lateral feed's,'thegrinding spindle 3 rotating in fixed bearing of the carriage. This givesrigidity combined with lightness, and minimizes. vibration. Ballbearings, as Hessbright or other type, are used for the grindingspindle.

In accordance with the best constructions embodying the principles ofthe invention, a means for guidlng the carriage in its movement will beemployed which permits of ready adjustment, and which is not liable towear or abrasion from emery diist or other abradent which may work intothe interstices of the bed. The means will also be conducive to thesensitiveness and freerace-ways, and for this purpose I provide v pins66 which project through the race-ways at intervals, suchintervalscorresponding to a distance at least half the maximum travel ofthe carriage plus the distance or length occupied by one group of balls.In this way the different groups of balls are kept distributed along alength tof the carriage,

so that the latter is adequately supported at all points of its length.At the same time it.

is freely guide-d. with an almost frictionless movement and the natureof the ball and race-way relation in such that'there is no appreciablewear from any emerydust which may find its way into the race-ways. ofthe raceways 62 is adjustable in the bed of the -machine, being free tomove horizontally in its contained slot or groove and held at differentpositions of adjustment by the screws 70-. By adjusting these screws anylooseness may be taken out in both raceways simultaneously.

73 denotes strips of felt located over the race-ways 62, 63, and helddown bymetallie strips or weights. The purpose and effect is to precludethe entrance of emery into the race-ways.

In the use of the machine poweri's applied to the shaft 20by a pulley78; or to the shaft 18 by a motor (not shown) within the frame 6. Therotation of the drum is communicated to the grinding spindle or spindlesby a belt or belts 79 at a multiplying speed One" ratio, and on accountof the length of the drum 17 this driving ratio is preserved for anyposition of the carriage, the belt traveling along the drum to newpositions by a familiar principle. The emery or grinding wheel or cutter4 is carried on the grinding spindle, and I provide means by which avery small wheel or a very large wheel may be adequately supported. 80denotes a pin screwed into the end of the grinding spindle and adaptedto constitute a hub or axis on which a small grinding wheel may bereceived. It will be evident that such a small wheel is properlycentered and may have an outside diameter scarcely greater than theoutside diameter of the grinding spindle. This pin though adequate to.hold a small grinding wheel is too small to properly support a largewheel.

85 denotes a bushing preferably with a coned central hole adapted to beslipped over a correspondingly tapered end of the grindin spindle. Thisbushing has a screw collar 8 and is adapted to receive a large 25grinding wheel 88. The screw pin 80 in this case constitutes a means forholding the bushing on the spindle, a couple of washers or similar cap90 being interposed if desired.

Means are provided by which the rotation of the chuck spindle isarrested promptly, although not so abruptly as to throw off any of thebelts. It will be observed that the fork 52 of the bell crank 51, isengaged in a collar forming part of the clutch 29. As shown the clutch29 comprises a common type of which the outer casing rotates in onepiece or unit and is loose on the shaft 20. The inner member 92 is fixedto the shaft. The movement of the collar 53 shifts the entire clutchcasing 29 to the right so as to loosen the clutch at the engagin faces92, 93. At the same time the entire orce of .the spring 55 is broughtinto action to force the collar against the fork 52, and this produces afriction or braking action which promptly arrests the rotation of theclutch 29. The chuck spindle 1 is therefore stopped. promptly. Duringthe normal running of the machine however, the force of the spring 55 istaken up between the face 93 and the collar 56 so that there is no forceagainst any fixed bearing .to interfere with the rotation of this shaftor produce heating. It will be'understood that the chuck 2 may be of anydesired character but in order to cooperate with the other features ofthe invention the chuck 2 will be and is shown as an automatic chucksuch as described in Patent No. 927,424, filed July 6, 1909, or ourcopending application Serial No. 643,486, filed of even date herewith.In other words there will be a draw tube or rod within the spindle 1 andoperated as described in the patents just referred to. The result is tomove the jaws into and out of clamping relation on the work practicallysimultaneously with the stoppage of the rotation, and the jaws willfurthermore always clamp the work in an exact relation to a given centeror axis thereof.

What we claim is '1. In a machine of the class described, a chuckspindle, a grinding spindle, a transversely adjustable head-stock forsaid chuck spindle, a lon itudinall movable carriage for said grin ingspin le, and means for stopping the rotation of the chuck spindle whensaid carriage is moved beyond a predetermined range.

2. In a machine of the class described, a chuck spindle, a grindingspindle, a swiveled and transversel adjustable head stock for said chuckspindle, a longitudinally -movable carriage for said grinding spindle,

and means for stopping the rotation of said chuck spindle when the saidcarriage is moved beyond a predetermined range.

3. In a machine of the class described, a chuck spindle, a grindingspindle, an adj ustable head-stock for said chuck spindle, a constantlyrotating drum beneath said grinding spindle and belted thereto, said rumhaving a peripheral length equal to the travel of the carriage and alongitudinally movable carriage aving bearings for said grindingspindle.

n a machine of the class described, a

chuck spindle, a grinding spindle, a carriage for said grinding spindle,,a hand-lever connected to reciprocate said carriagelongitudinally, andmeans operated by a movement of the said hand-lever beyond apredeterminedrange for stopping the rotation of said chuck spindle.

5. Ina machine of'tlie class described a chuck spindle, drivingconnections-therefor including a clutch, a grinding spindle, ahand-lever for, moving said grinding spindle longitudinally, and meansincluding a slotted link connection for throwing out said clutch whensaid hand-lever is moved beyond a predetermined range.

6. In a machine of the class described, a chuck spindle, a grindingspindle, driving connections for said 'chuck spindle includin a clutch,a carriage for said grinding spindle having a rack on its'under side, ahand-lever having a segment gear meshing with said rack, a link, andmeans connecte to said link for throwing out said clutch when thecarriage moves beyond a predement for said link, said link being locatedto be on a dead center when at theend of its of two subscribingwitnesses, this 8th day of travel, whereby it is looked and held in thisAugust, 1911.

position, and means connected to said link for throwing out said clutchwhen the oargfi nL 5 riage moves beyond the predetermined C range. 1Witnesses In testimony whereof, we have signed our FREDERICK E. SEDDON,

names to this specification in the presence FRANK A. POWER.

